7.1

CVE-2021-20267: openstack neutron

CVSS: 7.1v3.1HighModified
AliasesGHSA-w8hx-f868-pvchPYSEC-2021-136UBUNTU-CVE-2021-20267
Published 28-05-2021Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-20267 is a high (CVSS 7.1) vulnerability in openstack neutron. EPSS estimates a 1.02% chance of exploitation in the next 30 days, higher than 62.9% of scored vulnerabilities.

Overall risk
29/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.1/10
010
High · v3.1 (NVD)
EPSS score
1.02%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
USN-6067-1

Timeline

  1. 28-05-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

A flaw was found in openstack-neutron's default Open vSwitch firewall rules. By sending carefully crafted packets, anyone in control of a server instance connected to the virtual switch can impersonate the IPv6 addresses of other systems on the network, resulting in denial of service or in some cases possibly interception of traffic intended for other destinations. Only deployments using the Open vSwitch driver are affected. Source: OpenStack project. Versions before openstack-neutron 15.3.3, openstack-neutron 16.3.1 and openstack-neutron 17.1.1 are affected.

CVSS metrics

6 scores · 4 sources · 3 versions

EPSS trend

Probability

1.02%

Chance of exploitation in the next 30 days

Percentile

63%

Versus all other CVEs

30-day change

0.00 pp

From 1.02% on 20-09-2026

20-09-202620-10-2026
EPSS score
1.02%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • neutron< 2:17.1.1-5
Openstack1 product
  • neutron< 16.3.3 | ≥ 17.0.0, < 17.1.3 | 18.0.0
PyPI1 product
  • neutron≥ 16.0.0, < 16.3.1 | < 15.3.3 | ≥ 17.0.0, < 17.1.1
Redhat1 product
Ubuntu1 product
  • neutronAll versions (No fix recorded) | < 2:12.1.1-0ubuntu8.1 | < 2:16.4.2-0ubuntu6.2

5 vendors · 5 products

References

11 links
Show all 11 references